The stomachs of ruminant animals (bovine, ovine, and caprine) are commonly used in the production of edible products as well as inedible products. The stomachs are collectively known as tripe after further processing. Ruminants have four anatomical stomachs which include first the fumen (paunch), secondly the reticulum (honeycomb), thirdly the omasum (bible), and lastly the abomasum or (rennet). After the viscera (stomachs and internal organs) are removed from the animal during slaughter, the organs and stomachs are manually separated and moved to their respective product area for processing and packaging. As for the stomachs, the abomasum is cut to separate it from the small intestines and the omasum. The omasum is then removed from the rumen and reticulum.
The processing of omasum tripe typically involves manual removal of most of the external fat and removal of a ridge portion. The omasum is then cut in half to expose the inside folds and then it is washed and refined. The washing process involves using agitation and water to remove the stomach contents (ingesta) and other material from the product. The refining process uses abrasion to remove any remaining fat, connective tissue or contaminant from the surface of the tripe. Bleaching chemicals can also be used during this process. The time and temperature of water used during washing and refining is dependent on the quality of tripe being produced and has a wide range. The abomasum portion is typically washed to remove contents and trimmed of fat by hand before packaging. Processing of the rumen and reticulum typically include hanging the paunch on a moving chain, followed by opening of the rumen and reticulum to remove the ingesta. The rumen and reticulum sometimes pass through a rinse system to help remove ingesta as well. Fat on the exterior surface of the stomach is removed by hand or left in place at this point. The reticulum can be separated from the rumen or left together during subsequent washing and refining as described above.
Conventional processing for removing the external fat and related material involves manual removal or no removal at all, which can be labor intensive and costly. Manual removal of fat does not always result in total removal, and the remaining fat then needs to be removed in the washing and refining process or by post-process trimming. It is therefore desirable to efficiently remove as much fat as possible prior to washing and refining thereby reducing processing time and minimizing damage to the final product(s).
Washing and refining processes are described in U.S. Pat. Nos. 3,958,304, 6,348,226, and 7,261,628, the entire disclosures of which are incorporated by reference for all purposes. The washing and refining steps are needed to produce the edible tripe products and are not used as a method to recover the external fat. By allowing fat to remain on the stomachs upon washing and refining, the recovery of this fat for subsequent sale is also greatly reduced as it is mostly emulsified and thus unrecoverable.